SC1088

Silan Semiconductors FM RECEIVER CIRCUIT FOR BATTERY SUPPLY DESCRIPTION The SC1088 is a bipolar integrated circuit for use in mono portable and pocket radios. It is used when a minimum of perpheral components (of small dimensions and low costs) is important. The circuit contains a frequency-locked-loop(FLL) system with an intermediate frequency(IF) of about 70kHz. Selectivity is achieved by active RC-filters. De-tuning related to the IF and too weak input signal is suppressed by the mute circuit. SC1088 FEATURES * Equipped with all stages of a mono receiver from antenna to audio output. * Mute Circuit * Search tuning with a single varicap diode * Mechanical tuning with integrating AFC * AM application supported * Power supply polarity protection * Power supply voltage down to 1.8V SOP-16 APPLICATION 1. Mechanical tuning: This is possible with or without integrated AFC circuit 2. Electrical tuning: This is realized by one directional(band-up) search tuning facility, including RESET to the lower-band limit. PIN CONFIGURATIONS MUTE VOAF LOOP VP OSC IF FB CLP1 VOIF 1 2 3 4 16 15 14 13 TUNE CAP GND CLIM VIRF VIRF CLP2 VIIF SC1088 5 6 7 8 12 11 10 9 HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD 1 180pF 3.9nF 330pF 0.1µF 470pF 3.3nF RUN 22nF BLOCK DIAGRAM 6 11 +1 70nH 6k 7 8 9 10 13 15 3 82pF 5.4k IF Limter All pass Filter V1 Mixer 5k 2.2k 2.2k 10k Silan Semiconductors 68pF 12 VP 220pF 5 Demodulator 78nH V101 VCO V2 SC1088 6k Loop Filter 680pF +3V HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD 4 10nF 2 V2 AF 14 & 16 R S Searching tuning -1 V2 5.6k AF V3 MUTE 68nF RESET 1 0.1µF 1.8nF 2 VoAF 22k Note: V1,V2 and V3 are internal voltages. SC1088 Fig.1 Block Dirgram and Application Circuit for Search Tuning. Silan Semiconductors ABSOLUTE MAXIMUM RATINGS Characteristic Supply Voltage Operating Temperature Storage Temperature SC1088 Symbol Vp Tamb Tstg Value 5 -10 ~ +70 -55 ~ +150 Unit V °C °C DC ELECTRICAL CHARACTERISTICS (Tamb=25°C,Vp=3V ,Unless otherwise specified) Parameter Symbol Supply Voltage(pin 4) Supply Current(Pin 4) DC voltage of pin 1 DC voltage of pin 3 DC voltage of pin 6 and 7 DC voltage of pin 8 DC voltage of pin 9,10 and 13 DC voltage of pin 11 and 12 DC voltage of pin 15 AF output current on pin 2 Oscillator current on pin 5 Vp Ip V1 V3 V6,7 V8 V9,10,13 V11,12 V15 I2 I5 Test conditions Min 1.8 4.2 2.50 2.64 2.38 1.60 2.42 0.91 2.06 45 275 Typ 3.0 5.2 2.55 2.69 2.44 1.67 2.47 0.94 2.12 60 375 Max 5.0 6.6 2.60 2.74 2.50 1.74 2.52 0.98 2.18 80 500 Unit V mA V V V V V V V µA µA AC ELECTRICAL CHARACTERISTICS Parameter Symbol Tamb=25°C,Vp=3V,Firf=96MHz modulated with ∆f=±22.5kHz and fm=1kHz deviation;EMF=0.3mV(e.m.f. at a sourse impedance of 75Ω),and measurement taken in fig.3 Unless otherwise specified Test conditions VoAF=-3dB;VoAF=0dB at Vi=1mV;see Fig. 2 Mute OFF Mute ON (S+N)/N=26dB THD